Electrical connector



Feb. 1, E, A OR ELECTRICAL CONNECTOR 2 SheeLts-Sheet 1 Filed Dec. 19, 1949 mfl i 7 M.

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ELECTRICAL CONNECTOR 2 Sheets-Sheet 2 Filed Dec. 19, 1.949

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#TTUP/VEY ELECTRICAL CONNECTOR Emil A. Horn, Garden City, N. Y., assignor to Russell & Stoll Company, Inc., New York, N. Y., a corporation of New York Application December 19, 1949, Serial No. 133,920

8 Claims. (Cl. 339-90) This invention relates to separable electrical connectors and more particularly to the electrical connectors of the automatic locking type.

The object of this invention is to provide an improved separable electrical connector.

Another object is to provide an electrical connector that may be easily disassembled and reassembled.

Another object is to provide an electrical connector having contacts that are simple in structure.

Another object is to provide a connecting sleeve that is more securely fastened to the connector casing.

A further object is to provide a connector with interchangeable insulating members.

Other objects and advantages of the invention will appear from the following description considered in connection with the accompanying drawings in which:

Fig. 1 is a perspective view of the connector;

Fig. 2 is a cross-sectional view of the socket along lines 22 of Fig. 1;

Fig. 3 is a cross-sectional view of the plug along lines 33 of Fig. 1;

Fig. 4 is a perspective view of the insulating member of the socket;

Fig. 5 is a perspective view of the insulating member of the plug;

Fig. 6 is a front view of a socket insulating member;

Fig. 7 is a rear view of a socket insulating member;

Fig. 8 is a perspective view of a wall socket;

Fig. 9 is a perspective view of the socket contact;

Fig. 10 is a perspective view of the prong or plug contact; and 11Fig. 11 is a cross-sectional view of Fig. 3 along line Referring to Fig. 1, there is shown a connector comprising a plug 21 and a socket 22 for connecting the cables 23, 24 in locked relation with one another. On insertion into the socket the plug locks automatically into engagement with the socket preventing the connector 20 from separating accidentally. The connector has an outer metal casing or housing for enclosing the electrical contacts mounted in inner insulating blocks or members. The socket 22 has an outer casing 26 and an inner insulating body 27 holding electrical contacts or sockets 29. The plug 21 has an outer casing 33 with a connecting sleeve 34 rotatably attached thereto. In the casing 33 the insulating body or block 35 holds the electrical contacts or prongs 36. On insertion of the plug into the socket the prongs 36 enter into the electrical sockets 29 and the connecting sleeve 34 telescopes into the socket casing 26 with the key 41 on the sleeve locking into the groove 42 on the casing 26.

The connector 20 is preferably of a cylindrical shape with the insulating members readily separated from their respective casings. The socket casing 26 extends over the insulating body 27. The face of the insulating body is even with the end of the casing. Longitudinally extending internal contact passages 45 are provided for the electrical socket contacts 29 within the contact supporting portion of the insulating member 27.

The contact socket 29 as shown in Fig. 9 is preferably made from a single piece of metal and comprises a split tubular engaging portion 55 and a terminal plate or portion 56 with a screw 57 for clamping the conductors of the cable 23. The engaging portion is preferably of a tubular shape with oppositely disposed longitudinal slits 58 to provide resiliency to the contact. The terminal nited States Patent 0 plate 56 is preferably flat and has a screw 57 (Fig. 2) mounted in an opening 49 in the center. The terminal plate and the tubular engaging portion are in the same general plane and are connected by a warped surface 59, that is, flat adjacent the terminal and cylindrical in contact with the engaging portions.

The tubular portion 55 fits into passage 45 of the contact supporting portion of the insulating body and engages a shoulder 61 (Fig. 2) formed by a short narrow portion 62 of the passage. This narrowed portion provides a non-conducting surface between the opening in the face of the insulating body and the conducting contact. The tubular contact fits loosely in the passage to permit the expansion of the split engaging members. On the end of the terminal plate is a transverse projection 64 perpendicular to the plate and extending inwardly. It is engaged by the disc shaped end engaging plate 48 to hold the contact against the shoulder 61 and in the insulating body. If it is desired to remove the contacts from the insulating body it is only necessary to remove the insulating body from the casing, detach the end plate and pull or drop the contacts out of the passages. Also the contacts can be easily secured in the insulating body by placing the contacts in the insulating body and bolting the end plate thereto.

The terminal recesses 50 (Figs. 4 and 7) are notched into the terminal portion 51 and have oppositely dis posed shoulders 65, 66 on opposite sides of the slot 67. The terminal plate 56 rests on these two shoulders and the center retaining projection 64 fits into slot 67 between the shoulders 65, 66. When the contact is in place the screw 57 that is mounted through the plate 56 extends into the slot 67.

As best illustrated in Figs. 6 and 7, the passage 55' in the insulating member 27 at the portion containing the contact 29 has a diameter of approximately one-fifth, or slightly less than one-fifth, of the outside diameter of the insulating body and the center of the passage 55 is approximately one-fourth the diameter of the insulating member from the outer edge of the insulating member. The portion 62 and the passages in the insulating member 35 are approximately one-eighth of the diameter of the insulating member.

In Fig. 7 the raised edges 60 are shown between the terminal recesses 50 on the outer edge of the terminal portion. The raised edges center the end plate 48 on the insulating body. The outer edge or rim of the end plate is inwardly of the terminal plate 56 so that it does not obstruct or interfere with the retention of the conductor of the cable on the terminal plate. The screw 54 fits through an opening in the center of the end plate and screws into the hole 53 in the center of the end of the insulating body. The terminal plate has outwardly extending wings 75, 76 to force or hold the conductors around the bolts 57.

As shown in Figs. 1 and 2, the outer casing 26 is a single shell that may be considered in three sections, locking section 79, retaining section 80 and a terminal chamber 81. The retaining section 80 is between the locking section and the terminal chamber and has an inward head grooved portion 82 against which the recessed shoulder 83 on the insulating body 27 engages to position the insulating body with the face flush with the rim or edge of the casing. The retaining section holds the insulating body. Screws 84 mounted thereon fit into grooves 86 extending longitudinally of the insulating body. The screws 84 engage the ends 88 of longitudinal grooves 86 and hold the shoulder 83 of the insulating body against the annular grooved portion 82 in the wall of the casing 26. A second shoulder is provided between the shoulder 83 and the outer surface of the terminal portion to hold the insulator ring 123 around the terminal.

Each of the grooves 86 (Fig. 4) is at a slight angle to a plane containing the axis of the insulating body and intersecting the groove. The screws 84 will tend to force the keyway 91 into the key 92 and securely hold the insulating body. The key and keyway also guide the insulating body and properly position the insulating body in the casing.

The locking section 79, as shown in Figs. 1 and 2, is

of a larger diameter than the insulating member 27 to provide a space between the casing and the insulating body. The locking section has an L-shaped groove 42 to receive the knob 41 on the connecting sleeve 34.

The terminal chamber formed by the walls 81 gives ample room for the terminal portion of the insulating body and the conductors of the cables. In the end wall 98 is a central opening 99 for the cable 23. A strain relief fitting fits in the opening with one fitting welded to the end wall and the other fitting loose to adjust the fittings for various size cables.

The insulating body of the plug 21 is similar to the insulating body 27 except that the insulating body 35 and the passages 37 therein are shorter and unobstructed (Figs. 3 and 5). The terminal recesses 104 are preferably of the same size and shape as the terminal recesses of the socket insulating member. As shown in Fig. 10, the prongs 36 have a cylindrical engaging portion 100 and a terminal plate or portion 101 connected to said cylindrical portion 100 in substantial alignment. On the end of the terminal plate 101 is a projection 102 perpendicular thereto and when the prong is in the insulating body the projection 102 is directed inwardly. The projection 102 is narrower than the terminal plate and on a side opposite to the cylindrical engaging portion. The insulating body 35 has a removable end retaining plate 105 similar to the end retaining plate 48 of the socket insulating body. The end plate 105 engages the projection 102 and holds the terminal plate 101 against the sides of the opening to the prong passages and holds the prong in the passage. The end plate 105 is held in place by the bolt 106.

The casing 33 has a retaining section 107 with screws 108 mounted through the wall of the retaining section into the grooves 110 of the insulating body. The screws hold the shoulder 111 against the annular inwardly extending groove 112.

The connecting sleeve 34 may be considered in three sections, the knurled section 113, the center section 114 and the insertable section 115. The sleeve is held on by two upstanding annular beads 116, 117 spaced from one another with a flat surface 109 in between. The edges of the knurled section are turned over the beads locking the connecting sleeve onto the casing while permitting rotational movement of the sleeve.

The center section 114 between the knurled section and the insertable section fits around the retaining section 107 of the casing and has two slots through which the retaining screws 108 may be inserted and tightened.

On the connection of the socket 22 and plug 21 the section fits into the space between the locking section '79 and the insulating body 27, the knob 41 engaging the inclined portion 52 of the groove 42 to turn the sleeve 34. The prongs fit part way into the passages to hold the casing 33 and the insulating body 34 fixed in relation to the socket 22.

A fiat spring 119 is attached at one end to the knurled section 113 (Fig. 11) and coiled around the casing 33 in the fiat groove between the beads 116, 117. The other end of the spring is bent to form a catch 120 that is inserted in an opening 121. The spring 119 permits a limited rotation of the sleeve in either direction. On a clockwise rotation of the sleeve the spring tightens around the casing 33. On a counterclockwise rotation the spring expands and presses against the inner wall of the knurled section. The normal position of the sleeve is with the spring 119 extended in the position indicated.

The faces of each of the insulating bodies have raised portions about the openings with grooves 126 in between the raised portions. Thus, each of the contacts is separated from an adjacent contact by a groove.

The terminal plate and the conductors of the cable are protected from accidentally contacting the metal casing by the ring 123 and the washer 124. The washer is preferably made of sponge or soft rubber and fits around the cable as it enters the casing. The ring may be made of cardboard or similar flexible material. The ring fits around the terminal portion of the insulating block and extends beyond the end thereof. The insulating body has a second shoulder 85 against which the insulating body engages holding the ring over the terminals. The ring is not fastened to the insulating body but it fits snugly on the terminal portion.

In the embodiment shown in Fig. 8 socket 129 is mounted on a wall plate 133. The socket comprises a casing 130 and an insulating body 136 in the casing. The casing is attached to the wall plate by the flanges 135. The casing has a locking section 131 and a retaining section 132. The locking section 131 fits into an opening 137 having a notch 138 for the locking groove 139. The flanges perpendicular to the wall plate 133 are welded to the locking section 131 and hold the socket securely in place. The flanges are attached to the casing adjacent the wall plate and preferably extend annularly around a substantial portion of the casing. The locking section is slightly larger in diameter than the insulating body to provide an annular space for the sleeve of the socket. The retaining section is slightly smaller than the locking section and has retaining screws 14 1 almost diametrically opposed through the wall into the insulating body and the end of the retaining section is turned or bent inwardly. The shoulder 142 of the insulating member engages the inturned edge of the retaining section positioning the insulating body axially.

The insulating body may be of the same structure as the one of the cable connector. The insulators 27, 35 and 136 fit in either of the casings 26 or 33 and in the wall casing 130. The terminal portion extends beyond the casing so that the terminals of the contacts are unobstructed and readily accessible.

What is claimed is:

I. An electrical contact comprising a cylindrically shaped engaging portion mountable in an insulating member, a flat terminal plate having a thickness less than said engaging portion and a width greater than said cylindrical engaging portion, said terminal plate and engaging portion being aligned for longitudinally extending in an insulating supporting member, said terminal plate having a projection on the end opposite the engaging portion, said projection extending in a plane transverse to said terminal plate and said engaging portion for retaining said piece in an insulating member.

2. In the socket of a separable connector a single piece cylindrical insulating member having a terminal portion and a contact portion with contact passages extending longitudinally through said contact portion, a recessed shoulder on the end of said contact portion adjacent said terminal portion for engaging an inward head, said terminal portion being of lesser diameter than said shoulder for receiving a ring-shaped insulating piece and having terminal recesses aligned with said contact passages, electrical contacts having cylindrical engaging portions fitting in said passages and a flat plate-shaped terminal portion positioned in said terminal recess integral with and in line with said contact portion, a transverse means at the end of said terminal portion opposite to said contact portion, a shoulder in said passage and a plate mounted on the end of the terminal portion cooperating with said means to hold said contacts in said passage.

3. In the socket of a separable connector a single piece cylindrical insulating member having a terminal portion and a con-tact portion with contact passages extending longitudinally through said contact portion, a recessed shoulder on the end of said contact portion adjacent said terminal portion for engaging an inward bead, said terminal portion being of lesser diameter than said shoulder for receiving a ring-shaped insulating piece and having terminal recesses aligned with said contact passages, electrical contacts having cylindrical engaging portions fitting in said passages and a fiat plate-shaped terminal portion wider than said passages and positioned in said terminal recess integral with and in line with said contact portion, a transverse projection on the end of each of said terminal portion opposite to said contact portion and extending inwardly, a shoulder in said passage and a plate mounted on the end of the terminal portion to engage said projection and hold said contacts in said passage.

4. A socket receptacle for a separable connector comprising a single piece cylindrically-shaped insulating member having a terminal portion and a contact portion with contact passages extending longitudinally through said contact portion, an outer tubular single piece casing of metal having an opening at one end through which said insulating member is insertable into said casing, a terminal chamber at the other end with an inward bead, said inward bead being intermediate of said casing and at the opening end of said terminal chamber, said insulating member having a recessed shoulder on the end of said contact portion adjacent said terminal portion engaging said inward bead to position said insulating member in said casing with the terminal portion in said terminal chamber and the end of said contact portion adjacent the end of the casing, said casing spaced from said contact portion to form an annular space to receive the telescoping casing of a complementary plug receptacle, said terminal portion having a diameter less than said shoulder for receiving a ring shaped insulating piece between said casing and said terminal portion and having terminal recesses aligned with said contact passages, electrical contacts having cylindrical engaging portions fitting in said passages and flat plate-shaped terminals integral with and in line with respective engaging portions, a transverse projection on the end of each of said terminal portions opposite a respective contact portion and extending inwardly, a shoulder in said passage and a plate secured on the end of said terminal portion to engage said projection and hold said contacts in said passage against said shoulder.

5. A socket receptacle for a separable connector comprising a single piece cylindrically-shaped insulating member having a contact portion, a terminal portion of lesser diameter than said contact portion, evenly spaced cylindrical passages extending longitudinally through said contact portion and evenly spaced terminal recesses in said terminal portion aligned with respective passages, an outer tubular single piece casing of metal having an interlocking wall, a retaining wall and a terminal chamber wall, an inner bead in said casing between said retaining wall and said terminal chamber wall, said contact portion having a recessed shoulder adjacent the terminal end engaging said inner bead to position said insulating member longitudinally with respect to the outer casing and placing the terminal portion within the terminal chamber wall and said contact portion within said retaining wall and said interlocking wall, said interlocking wall spaced from said contact portion to form an annular space to telescopically receive a complementary interlocking plug casing, electrical contacts each having a cylindrical engaging portion fitting in a respective passage and a flat plate-shaped terminal formed in line with said engaging portion, an inwardly extending transverse projection on the end of each of said terminal portions opposite said engaging portions, a shoulder in said passage and a discshaped plate secured to the end of said terminal portion to engage said projection and hold said contacts in said passage against said shoulder, said plate having an outer periphery not greater in radial distance than the terminal plate to provide a space at said terminal recesses for wires connected to said contacts.

6. A separable connector comprising a single piece cylindrical insulating member having a terminal portion and a contact portion with contact passages extending longitudinally through said contact portion, said terminal portion having recesses aligned with said contact passages, electrical contacts having cylindrical engaging portions fitting in said passages and a flat terminal plate wider than the diameter of said passage to engage the contact portion for preventing forward displacement positioned in one of said recesses, said terminal plate being integral with and in line with said engaging portion, a transverse means at the end of said terminal plate opposite to the contact and a retaining plate fastened to said terminal portion engaging said transverse means for preventing rearward displacement of said electrical contact.

7. In combination with an electrical contact as set forth in claim 1, a single piece cylindrical insulating member having a terminal portion and a contact portion with contact passages extending longitudinally through said contact portion and having a diameter for holding said engaging portion, said terminal portion having recesses aligned with said contact passages, said engaging portions fitting in said contact passages for receiving a complementary engaging portion and said terminal plate positioned in said recesses for fastening to a cable, said passages centered approximately one-quarter of the diameter of the insulating member from the edge of said member to electrically space and mechanically support said contacts, means at the retaining means integral with said terminal portion engaging said projection for preventing rearward displacement of said electrical contact.

8. In combination with a plurality of electrical contacts as set forth in claim 1, a cylindrically-shaped insulating member having a terminal portion and a contact portion with contact passages extending longitudinally through said contact portion into which the engaging portions of said contacts respectively fit, said terminal portion having recesses aligned with said contact passages, said engaging portions fitting in a respective contact passage for receiving complementary engaging portions and said terminal plates being positioned in said recesses for connecting a cable thereto, said passages centered approximately one-quarter of the diameter of the insulating member to electrically space and mechanically support said contacts, each of said recesses having shoulders positioned radially inward approximately one-quarter of the diameter of the insulating member from the outer surface of said contact portion to recess the terminal and connections thereto inwardly of the outer surface of said terminal portion, and retaining means integral with said terminal portion to engage said projection to hold said contacts in said passage.

References Cited in the file of this patent UNITED STATES PATENTS 2,053,136 De Reamer Sept. 1, 1936 2,183,651 Langston et a1 Dec. 19, 1939 2,247,386 John July 1, 1941 2,281,654 Wulle et a1. May 5, 1942 2,291,808 Henning Aug. 4, 1942 2,312,002 Schmitt Feb. 23, 1943 2,411,861 Antony, Jr., et al. Dec. 3, 1946 

